Perhaps you should try some spelling variations:
ban nhanh » ban hanh, ban thanh, ban nhan
te sach » toc sach
ky tang » ky nang, kho tang, ky trong
ky dang » ky nang, ky danh
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
duc ban » duc tan, duc van, dua ban
hoa cua » hoa chat, hoa xuat
ha cua » hai cua, nha cua, ham cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((ky tang) or (ky dang)) xa hoi. hieu va cac duc ban nhanh ((ha cua) OR (hoa cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ky tang) OR (ky dang)) xa hoi. hieu va cac duc ban nhanh ((ha cua) OR (hoa cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ky tang) or (ky dang)) xa hoi. hieu va cac duc ban nhanh ((ha cua) OR (hoa cua)) triet".
• Adding a wildcard symbol may retrieve word variants: te sach ((ky tang) or (ky dang)) xa hoi. hieu va cac duc ban nhanh ((ha cua) OR (hoa cua)) triet*.